(1-substituted-indol-3-yl) alkylidenehydrazinecarboximidamide derivatives as 5-hydroxytryptamine-6 ligands

ABSTRACT

The present invention provides a compound of formula I and the use thereof for the therapeutic treatment of a disorder relating to or affected by the 5-HT6 receptor.

This application claims priority from copending provisional application Ser. No. 60/379,487, filed May 10, 2002, the entire disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

Various central nervous system disorders such as anxiety, depression, motor disorders, etc., are believed to involve a disturbance of the neurotransmitter 5-hydroxytryptamine (5-HT) or serotonin. Serotonin is localized in the central and peripheral nervous systems and is known to affect many types of conditions including psychiatric disorders, motor activity, feeding behavior, sexual activity, and neuroendocrine regulation among others. The effects of serotonin are regulated by the various 5-HT receptor subtypes. Known 5-HT receptors include the 5-HT1 family (e.g. 5-HT1A), the 5-HT2 family (e.g. 5-HT2A), 5-HT3, 5-HT4, 5-HT5, 5-HT6 and 5-HT7 subtypes.

The recently identified human 5-hydroxytryptamine-6 (5-HT6) receptor subtype has been cloned, and the extensive distribution of its mRNA has been reported. Highest levels of 5-HT6 receptor mRNA have been observed in the olfactory tubercle, the striatum, nucleus accumbens, dentate gyrus and CA1, CA2 and CA3 regions of the hippocampus. Lower levels of 5-HT6 receptor mRNA are seen in the granular layer of the cerebellum, several diencephalic nuclei, amygdala and in the cortex. Northern blots have revealed that 5-HT6 receptor mRNA appears to be exclusively present in the brain, with little evidence for its presence in peripheral tissues. The high affinity of a number of antipsychotic agents for the 5-HT6 receptor, in addition to its mRNA localization in striatum, olfactory tubercle and nucleus accumbens suggests that some of the clinical actions of these compounds may be mediated through this receptor. Therefore, 5-HT6 receptor ligands are believed to be of potential use in the treatment of certain CNS disorders such as anxiety, depression, epilepsy, obsessive compulsive disorder, attention deficit disorder, migraine, cognitive memory enhancement (e.g. for the treatment of Alzheimer's disease), sleep disorders, feeding disorders (e.g. anorexia or bulimia), neurodegenerative disorders (e.g. stroke or head trauma), panic attacks, withdrawal from drug abuse (e.g. cocaine, ethanol, nicotine or benzodiazepines), schizophrenia, or the like; or in the treatment of certain gastrointestinal disorders such as irritable bowel syndrome.

Therefore, it is an object of this invention to provide compounds which are useful as therapeutic agents in the treatment of a variety of central nervous system disorders related to or affected by the 5-HT6 receptor.

It is another object of this invention to provide therapeutic methods and pharmaceutical compositions useful for the treatment of central nervous system disorders related to or affected by the 5-HT6 receptor.

It is a feature of this invention that the compounds provided may also be used to further study and elucidate the 5-HT6 receptor.

These and other objects and features of the invention will become more apparent by the detailed description set forth hereinbelow.

SUMMARY OF THE INVENTION

The present invention provides a (1-substituted-indol-3-yl) alkylidene-hydrazinecarboximidamide compound of formula I

wherein

-   -   X is N or CR₃;     -   Y is N or CR₄;     -   R₁, R₂, R₃ and R₄ are each independently H, halogen, CN,         NR₁₁SO₂OR₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀,         NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl,         C₂-C₆alkynyl, C₃-C₆-cycloalkyl, cycloheteroalkyl, aryl or         heteroaryl group each optionally substituted;     -   R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a         C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted or R₅ and R₆ maybe taken together with the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring;     -   R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each         optionally substituted;     -   R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl         or heteroaryl group each optionally substituted or R₈ and R₉ may         be taken together with the atoms to which they are attached to         form an optionally substituted 5- to 7-membered ring optionally         containing one or two heteroatoms selected from O, N or S with         the proviso that when all of R₁, R₂, R₃ and R₄ are other than         NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or         heteroaryl group or taken together with R₈ and the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring optionally containing one or two heteroatoms         selected from O, N or S;     -   R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each         optionally substituted;     -   n is 0 or an integer of 1 or 2;     -   R₁₂ is an optionally substituted aryl or heteroaryl group;     -   R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or         a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted;     -   R₁₅ and R₁₆ are each independently H or an optionally         substituted C₁-C₆alkyl group; and     -   R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an         optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be         taken together with the atom to which they are attached to form         a 5- to 7-membered ring optionally containing another heteroatom         selected from O, N or S; or         the stereoisomers thereof, the tautomers thereof or the         pharmaceutically acceptable salts thereof.

The present invention also provides methods and compositions useful for the therapeutic treatment of central nervous system disorders related to or affected by the 5-HT6 receptor.

DETAILED DESCRIPTION OF THE INVENTION

The 5-hydroxytryptamine-6 (5-HT6) receptor is one of the most recent receptors to be identified by molecular cloning. Its ability to bind a wide range of therapeutic compounds used in psychiatry, coupled with its intriguing distribution in the brain has stimulated significant interest in new compounds which are capable of interacting with or affecting said receptor. Significant efforts are being made to understand the possible role of the 5-HT6 receptor in psychiatry, cognitive dysfunction, motor function and control, memory, mood and the like. To that end, compounds which demonstrate a binding affinity for the 5-HT6 receptor are earnestly sought both as an aid in the study of the 5-HT6 receptor and as potential therapeutic agents in the treatment of central nervous system disorders, for example see C. Reavill and D. C. Rogers, Current Opinion in Investigational Drugs, 2001, 2(1):104-109, Pharma Press Ltd.

Surprisingly, it has now been found that (1-substituted-indol-3-yl)alkylidene-hydrazinecarboximidamide derivatives of formula I demonstrate 5-HT6 affinity. Advantageously, said amide derivatives may be used as effective therapeutic agents for the treatment of central nervous system (CNS) disorders associated with or affected by the 5-HT6 receptor. Accordingly, the present invention provides (1-substituted-indol-3-yl)alkylidenehydrazinecarboximidamide derivatives of formula I

wherein

-   -   X is N or CR₃;     -   Y is N or CR₄;     -   R₁, R₂, R₃ and R₄ are each independently H, halogen, CN,         NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO₁₁R₂₀,         NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl,         C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or         heteroaryl group each optionally substituted;     -   R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a         C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted or R₅ and R₆ maybe taken together with the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring;     -   R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each         optionally substituted;     -   R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl         or heteroaryl group each optionally substituted or R₈ and R₉ may         be taken together with the atoms to which they are attached to         form an optionally substituted 5- to 7-membered ring optionally         containing one or two heteroatoms selected from O, N or S with         the proviso that when all of R₁, R₂, R₃ and R₄ are other than         NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or         heteroaryl group or taken together with R₈ and the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring optionally containing one or two heteroatoms         selected from O, N or S;     -   R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each         optionally substituted;     -   n is 0 or an integer of 1 or 2;     -   R₁₂ is an optionally substituted aryl or heteroaryl group;     -   R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or         a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted;     -   R₁₅ and R₁₆ are each independently H or an optionally         substituted C₁-C₆alkyl group; and

R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be taken together with the atom to which they are attached to form a 5- to 7-membered ring optionally containing another heteroatom selected from O, N or S; or

the stereoisomers thereof, the tautomers thereof or the pharmaceutically acceptable salts thereof.

As used in the specification and claims, the term halogen designates Br, Cl, I or F and the term cycloheteroalkyl designates a C₅-C₇cycloalkyl ring system containing 1 or 2 heteroatoms, which may be the same or different, selected from N, O or S and optionally containing one double bond. Exemplary of the cycloheteroalkyl ring systems included in the term as designated herein are the following rings wherein W is NR, O or S; and R is H or an optional substituent as described hereinbelow.

Similarly, as used in the specification and claims, the term heteroaryl designates a C₅-C₁₀ aromatic ring system containing 1, 2 or 3 heteroatoms, which may be the same or different, selected from N, O or S. Such heteroaryl ring systems include pyrrolyl, azolyl, oxazolyl, thiazolyl, imidazolyl, furyl, thienyl, quinolinyl, isoquinolinyl, indolinyl, benzothienyl, benzofuranyl, benzisoxazolyl or the like. The term aryl designates carbocyclic aromatic ring systems such as phenyl, naphthyl, or the like. The term haloalkyl as used herein designates a C_(n)H_(2n+1) group having from one to 2n+1 halogen atoms which may be the same or different and the term haloalkoxy as used herein designates an OC_(n)H_(2n+1) group having from one to 2n+1 halogen atoms which may be the same or different.

In the specification and claims, when the terms C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₇cycloalkyl, cycloheteroalkyl, aryl or heteroaryl are designated as being optionally substituted, the substituent groups which are optionally present may be one or more of those customarily employed in the development of pharmaceutical compounds or the modification of such compounds to influence their structure/activity, persistence, absorption, stability or other beneficial property. Specific examples of such substituents include halogen atoms, nitro, cyano, thiocyanato, cyanato, isocyanato, hydroxyl, alkyl, haloalkyl, alkoxy, haloalkoxy, amino, alkylamino, dialkylamino, formyl, alkoxycarbonyl, carboxyl, alkanoyl, alkylthio, alkylsulfinyl, alkylsulfonyl, carbamoyl, alkylamido, phenyl, phenoxy, benzyl, benzyloxy, cycloheteroalkyl or cycloalkyl groups, preferably halogen atoms or lower alkyl groups. Typically, 0-3 substituents may be present. When any of the foregoing substituents represents or contains an alkyl substituent group, this may be linear or branched and may contain up to 12, preferably up to 6, more preferably up to 4 carbon atoms.

Pharmaceutically acceptable salts may be any acid addition salt formed by a compound of formula I and a pharmaceutically acceptable acid such as phosphoric, sulfuric, hydrochloric, hydrobromic, citric, maleic, malonic, mandelic, succinic, fumaric, acetic, lactic, nitric, sulfonic, p-toluene sulfonic, methane sulfonic acid or the like.

Compounds of the invention include esters, carbamates or other conventional prodrug forms, which in general, are functional derivatives of the compounds of the invention and which are readily converted to the inventive active moiety in vivo. Correspondingly, the method of the invention embraces the treatment of the various conditions described hereinabove with a compound of formula I or with a compound which is not specifically disclosed but which, upon administration, converts to a compound of formula I in vivo. Also included are metabolites of the compounds of the present invention defined as active species produced upon introduction of these compounds into a biological system.

Compounds of the invention may exist as one or more stereoisomers. The various stereoisomers include enantiomers, diastereomers, atropisomers and geometric isomers. One skilled in the art will appreciate that one stereoisomer may be more active or may exhibit beneficial effects when enriched relative to the other stereoisomer(s) or when separated from the other stereoisomer(s). Additionally, the skilled artisan knows how to separate, enrich or selectively prepare said stereoisomers. Accordingly, the present invention comprises compounds of formula I, the stereoisomers thereof and the pharmaceutically acceptable salts thereof. The compounds of the invention may be present as a mixture of stereoisomers, individual stereoisomers, or as an optically active or enantiomerically pure form.

Preferred compounds of the invention are those compounds of formula I wherein R₁₀ is H. Also preferred are those compounds of formula I wherein R₂ is NR₁₁SO₂R₁₂. Another group of preferred compounds of formula I are those compounds wherein R₉ is an optionally substituted phenyl group or R₈ and R₉ are taken together with the atoms to which they are attached to form a 5- to 7-membered ring.

More preferred compounds of the invention are those compounds of formula I wherein R₁₀ is H and R₉ is an optionally substituted phenyl group. Another group of more preferred compounds are those compounds of formula I wherein R₁₀ is H and R₂ is NR₁₁SO₂R₁₂. Further more preferred compounds are those formula I compounds wherein R₁₀ is H, R₂ is H, C₁-C₆alkoxy or NR₁₁SO₂R₁₂; and R₉ is an optionally substituted phenyl group or R₈ and R₉ may be taken together to form a 5- to 7-membered ring.

Exemplary of the compounds of the invention are:

-   (Z)-2-[1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximid-amide; -   2-((Z)-1-{1-methyl-5-[(phenylsulfonyl)amino]-1H-indol-3-yl}ethylidene)hydrazinecarboximidamide; -   (Z)-2-[1-[5-[(4-biphenylsulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; -   (Z)-2-[1-[5-[(4-bromobenzenesulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; -   (Z)-2-[1-[5-[(5-bromothiophene-2-sulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; -   (Z)-2-[1-[5-[(5-chloro-2-methoxybenzenesulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; -   (Z)-2-[1-[5-[(2,5-dichlorobenzenesulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; -   (Z)-2-{cyclohexyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]methylidene}hydrazinecarboximidamide; -   (Z)-2-{2-methyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]propylidene}hydrazinecarboximidamide; -   (Z)-2-{2-phenyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]ethylidene}hydrazinecarboximidamide; -   (Z)-2-{3-methyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]butylidene}hydrazinecarboximidamide; -   2-[1-[5-[(phenylsulfonyl)amino]-1H-indole-3-carbaldehyde]-1,4,5,6-tetrahydro-pyrimidin-2-ylhydrazone; -   2-[1-[5-[(phenylsulfonyl)amino]-1H-indole-3-carbaldehyde]-4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   2-(2-phenyl-1H-indol-3-ylmethylene)hydrazinecarboximidamide; -   2-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]hydrazinecarboximidamide; -   N-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]-N′-(1,4,5,6-tetrahydropyrimidin-2-yl)hydrazine; -   N′-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]-N′-(4,5-dihydro-1H-imidazol-2-yl)hydrazine; -   2-[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-ylmethylene]hydrazinecarboximidamide; -   N′-[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-ylmethylene]-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N′-(2-phenyl-1H-indol-3-ylmethylene)-N-methylhydrazine; -   2-{[2-(naphthalen-2-yl)-1H-indol-3-yl]methylene}hydrazinecarboximidamide; -   2-[2-(4-fluorophenyl)-1H-indol-3-ylmethylene]hydrazinecarboximidamide; -   2-[1-(2-phenyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-2-(4-chloro-phenyl)-ethylidene}hydrazinecarboximidamide; -   2-[cyclohexyl-(2-phenyl-1H-indol-3-yl)-methylene]hydrazinecarboximidamide; -   2-{[2-(4-chloro-phenyl)-1H-indol-3-yl]-cyclohexyl-methylene}hydrazinecarboximidamide; -   2-{[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-yl]-cyclohexyl-methylene}hydrazinecarboximidamide; -   2-{[2-(4-chloro-phenyl)-1H-indol-3-yl]-2-methyl-propylidene}hydrazinecarboximidamide; -   2-{[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-yl]-propylidene}hydrazinecarboximidamide; -   2-[2-phenyl-1-(2-phenyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-2-phenyl-ethylidene}hydrazinecarboximidamide; -   2-{1-[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-yl]-2-phenyl-ethylidene}hydrazinecarboximidamide; -   2-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-3-methyl-butylidene}hydrazinecarboximidamide; -   2-{3-(2-chloro-phenyl)-1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-allylidene}hydrazinecarboximidamide; -   2-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{1-[2-(3-chloro-4-fluoro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   N′-[(4-chlorophenyl)-(2-phenyl-1H-indol-3-yl)-methylene]-N-(4,5,-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N′-{(4-chlorophenyl)-[2-(4-chlorophenyl)-1H-indol-3-yl]-methylene}-N-(4,5,-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N-methyl-N′-[3-methyl-1-(2-phenyl-1H-indol-3-yl)-but-2-enylidene]hydrazine; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N-methyl-N′-[3-phenyl-1-(2-phenyl-1H-indol-3-yl)-propylidene]hydrazine; -   N′-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-3-phenyl-propylidene}-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N-methyl-N′-[3-phenyl-1-(2-phenyl-1H-indol-3-yl)-allylidene]hydrazine; -   N′-{1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-3-phenyl-allylidene}-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N′-{2-(4-chloro-phenyl)-1-[2-(4-chloro-phenyl)-1H-indol-3-yl]-ethylidene}-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-[cyclohexyl-(1-methyl-2-phenyl-1H-indol-3-yl)-methylene]hydrazinecarboximidamide; -   2-[cyclohexyl-(1,2-diphenyl-1H-indol-3-yl)-methylene]hydrazinecarboximidamide; -   2-[1-(1-methyl-2-phenyl-1H-indol-3-yl)-2-methyl-propylidene]hydrazinecarboximidamide; -   2-[1-(1,2-diphenyl-1H-indol-3-yl)-2-methyl-propylidene]hydrazinecarboximidamide; -   2-[1-(1-methyl-2-phenyl-1H-indol-3-yl)-2-phenyl-ethylidene]hydrazinecarboximidamide; -   2-[1-(1,2-diphenyl-1H-indol-3-yl)-2-phenyl-ethylidene]hydrazinecarboximidamide; -   2-[1-(1-methyl-2-phenyl-1H-indol-3-yl)-2-methyl-butylidene]hydrazinecarboximidamide; -   2-[1-(1-methyl-2-phenyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-[1-(1,2-diphenyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-[3-(2-chloro-phenyl)-1-(1,2-diphenyl-1H-indol-3-yl)-allylidene]hydrazinecarboximidamide; -   2-[(1-methyl-2-phenyl-1H-indol-3-yl)-methylene]hydrazinecarboximidamide; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N′-[(1-methyl-2-phenyl-1H-indol-3-yl)-methylene]-N-methylhydrazine; -   2-[(1,2-diphenyl-1H-indol-3-yl)-methylene]hydrazinecarboximidamide; -   N-(4,5-dihydro-1H-imidazol-2-yl)-N′-[(1,2-diphenyl-1H-indol-3-yl)-methylene]-N-methylhydrazine; -   2-{1-[2-(4-fluoro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{1-[2-(3,4-difluoro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{1-[2-(naphthylen-2-ylmethyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[1-(2-phenethyl)-2-phenyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{1-[1-benzyl-2-(4-chloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[1-benzyl-2-(4-chloro-phenyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[1-benzyl-2-(4-chloro-phenyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[1-(2-chloro-benzyl)-2-(4-chloro-phenyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[1-(2-chloro-benzyl)-2-(4-chloro-phenyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[2-(4-chloro-phenyl)-1-(4-methyl-benzyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[2-(4-chloro-phenyl)-1-(4-methyl-benzyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-(1-{2-(4-chlorophenyl)-1-[(2-methyl-1,3-thiazol-4-yl)methyl]-1H-indol-3-yl}ethylidene)-1hydrazinecarboximidamide; -   2-({2-(4-chlorophenyl)-1-[(2-methyl-1,3-thiazol-4-yl)methyl]-1H-indol-3-yl}methylidene)-1hydrazinecarboximidamide; -   {[2-(4-chlorophenyl)-1((2-methyl-thiazol-4-yl)methyl)-1H-indol-3-yl]methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[2-(4-chloro-phenyl)-1-ethyl-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[2-(4-chloro-phenyl)-1-ethyl-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[2-(4-chloro-phenyl)-1-(2-methyl-propyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[2-(4-chloro-phenyl)-1-(2-methyl-propyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{1-[2-(4-chloro-phenyl)-1-(2-cyano-ethyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-chloro-phenyl)-1-(2-cyano-ethyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[2-(4-chloro-phenyl)-1-(2-cyano-ethyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[2-(4-chloro-phenyl)-1-(2-phenethyl)-1H-indol-3-yl]-methylene}hydrazinecarboximidamide; -   N-{[2-(4-chloro-phenyl)-1-(2-phenethyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   N-{[1-(3-butenyl)-2-(4-chloro-phenyl)-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-propyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-(2-hydroxyethyl)-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-(2-hydroxyethyl)-N′-methyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-cyclopentyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-cyclopentyl-N′-methyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-benzyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-benzyl-N′-methyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N′-methyl-N-propyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-methyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N,N′-dimethyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-pentyl-1hydrazinecarboximidamide; -   2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N′-methyl-N-pentyl-1hydrazinecarboximidamide; -   2-{[5-chloro-2-(2,4-dichloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(2,4-dichloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-bromo-2-(2,4-dichloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(p-tolyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-bromo-2-(p-tolyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(2-(3-methyl-thienyl))-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-bromo-phenyl)-5-chloro-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-bromo-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-bromo-2-(4-bromo-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-bromo-2-(4-chloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-methoxy-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(3-thienyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-bromo-2-(3-thienyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-[(2-biphenyl-5-chloro-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-{[5-chloro-2-(3,4-dichloro-phenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-chloro-2-(2,4-dichloro-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-[(2-biphenyl-5-chloro-1-methyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; -   2-{[5-chloro-2-(3,4-dichloro-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(3,4-dichloro-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[1-methyl-2-(2-(3-methyl-thienyl))-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-bromo-phenyl)-5-chloro-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-bromo-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[5-chloro-2-(4-chloro-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-{[2-(4-chloro-phenyl)-1-methyl-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; -   2-(2-(2-pyridyl)-1H-indol-3-ylmethylene)hydrazine carboximidamide; -   2-(2-(4-pyridyl)-5-bromo-1H-indol-3-ylmethylene)hydrazinecarboximidamide; -   2-(2-(indol-3yl)-1H-indol-3-ylmethylene)hydrazinecarboximidamide; -   2-(2-(3-ethyl-5-methyl-4-isoxazolyl)-1H-indol-3-ylmethylene)hydrazine-carboximidamide; -   2-(6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-ylhydrazone; -   6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   2-(6-fluoro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   6-fluoro-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-ylhydrazone; -   6-fluoro-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   2-(6-bromo-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   6-bromo-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   2-(1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   N′-(6-methoxy-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)carbonohydrazonic     diamide; -   2-(2,2,6-trimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-methyl-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-isopropyl-2,2-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-isopropyl-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4ylidene)hydrazinecarboximidamide; -   2-[2,2-dimethyl-6-(trifluoromethoxy)-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene]hydrazinecarboximidamide; -   2-(6-bromo-2,2-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-bromo-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-chloro-2,2-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-chloro-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-fluoro-2,2-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2,2,6-trimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)-hydrazone; -   6-methyl-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)-hydrazone; -   6-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   6-isopropyl-2,2-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; -   6-isopropyl-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl-(methyl)hydrazone; -   6-isopropyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)-hydrazone; -   6-fluoro-2-phenyl-1,2,3,9-tetrahydro-4H-carbazol-4-one     4,5-dihydro-1H-imidazol-2-yl(methyl)-hydrazone; -   7-chloro-3,4-dihydrocyclopenta[b]indol-1(2h)-one     4,5-dihydro-1H-imidazol-2-yl(methyl)-hydrazone; -   2-(6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)-N-pentylhydrazinecarboximidamide; -   N-benzyl-2-(6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; -   2-(6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)-N-cyclopentylhydrazinecarboximidamide; -   or the stereoisomers thereof or the pharmaceutically acceptable     salts thereof.

Compounds of the invention may be prepared using conventional synthetic methods and, if required, standard separation and isolation techniques. For example, compounds of formula I wherein R₈ is H and R₁₀ is other than H (Ia) may be prepared by reacting a compound of formula IV with dimethylformamide (DMF) and phosporous oxychloride to give the 3-carboxaldehyde of formula V, alkylating or arylating the formula V compound with the appropriate alkyl or aryl halide in the presence of a base to give the 1-substituted-indol-3-yl compound of formula VI and reacting the formula VI compound with an aminoguanidine derivative of formula III to give the desired product of formula Ia. The reaction sequence is shown in flow diagram I wherein Hal represents Cl, Br or I.

Similarly, compounds of formula I wherein R₈ is an optionally substituted alkyl or cyclbalkyl group and R₁₀ is other than H (Ib) may be prepared by acylating a formula IV compound with an acyl halide, R₈CO-Hal to give the 3-acyl compound of formula VII, alkylating or arylating the formula VII compound, and reacting the resultant product with an aminoguanidine derivative of formula III, as described in flow diagram I, to give the desired formula Ib product. The reaction is shown in flow diagram II wherein Hal represents Cl, Br or I.

Compounds of formula I wherein R₈ and R₉ are taken together with the atoms to which they are attached to form a six-membered ring and R₁₀ is other than H (Ic) may be prepared by reacting 1,3-cyclohexanedione with a hydrazine of formula VIII to form the hydrazone of formula IX, heating said formula IX hydrazone in the presence of trifluoroacetic acid (TFA) to form the oxocarbazole of formula X, and sequentially alkylating the formula X compound and reacting the alkylated product with an aminoguanidine derivative as described hereinabove to give the desired compound of formula Ic. The reaction scheme is shown in flow diagram III wherein Hal is Cl, Br or I.

Compounds of formula I wherein R₈ and R₉ are taken together to form a 5- or 7-membered ring (Id) may be prepared by the regioselective oxidation of a ring fused indole system as described by Oikawa et al, Heterocyclic, 1976, 4, 1959 and Comp. Het. Chem., 1984, 4, 253 to give the intermediate of formula XI which may be converted to the desired formula (Id) product. The reaction scheme is shown in flow diagram IV wherein m is 1, 2 or 3.

Compounds of formula I wherein R₁₀ is H may be prepared as described hereinabove and deleting the alkylation arylation step.

Azaindoles such as 4-azaindole or 7-azaindole may be prepared by methods described in the literature, i.e., I. Mahadevan, I., Rasmussen, M., J. Het. Chem., 1992, 29, 359-367; Hands, D.; Bishop, B.; Cameron, M.; Edwards, J. S.; Cottrell, I. F.; Wright, S. H. B., Synthesis, 1996, 877-882; Dobson, D.; Todd, A.; Gilmore, J., Synth. Commum. 1991, 21, 611-167. In addition, azaindoles are also available commercially.

Advantageously, the present invention provides a process for the preparation of a compound of formula I which comprises reacting a compound of formula II with an aminoguanidine derivative of formula III in the presence of an acid, optionally in the presence of a solvent. The process is shown in flow diagram V.

Acids suitable for use in the process of the invention include acids such as HCl, HBr, H₂SO₄, HNO₂ or the like, preferably HCl. Solvents suitable for use in the process of invention include protic solvents such as lower alkyl alcohols, i.e., methanol, ethanol, isopropanol, n-propanol or the like, preferably isopropanol.

Advantageously, the inventive compound of formula I may be utilized in the treatment of central nervous system disorders relating to or affected by the 5-HT6 receptor such as motor, mood, psychiatric, cognitive, neurodegenerative, or the like disorders, for example, Alzheimer's disease, Parkinson's disease, attention deficit disorder, anxiety, epilepsy, depression, obsessive compulsive disorder, sleep disorders, neurodegenerative disorders (such as head trauma or stroke), feeding disorders (such as anorexia or bulimia), schizophrenia, memory loss, disorders associated with withdrawal from drug or nicotine abuse, or the like. Accordingly, the present invention provides a method for the treatment of a disorder of the central nervous system related to or affected by the 5-HT6 receptor in a patient in need thereof which comprises providing said patient a therapeutically effective amount of a compound of formula I

wherein

-   -   X is N or CR₃;     -   Y is N or CR₄;     -   R₁, R₂, R₃ and R₄ are each independently H, halogen, CN,         NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀,         NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl,         C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or         heteroaryl group each optionally substituted;     -   R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a         C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted or R₅ and R₆ maybe taken together with the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring;     -   R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each         optionally substituted;     -   R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl         or heteroaryl group each optionally substituted or R₈ and R₉ may         be taken together with the atoms to which they are attached to         form an optionally substituted 5- to 7-membered ring optionally         containing one or two heteroatoms selected from O, N or S with         the proviso that when all of R₁, R₂, R₃ and R₄ are other than         NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or         heteroaryl group or taken together with R₈ and the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring optionally containing one or two heteroatoms         selected from O, N or S;     -   R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each         optionally substituted;     -   n is 0 or an integer of 1 or 2;     -   R₁₂ is an optionally substituted aryl or heteroaryl group;     -   R₁₃, R₁₄, R₁₈, R₂₀ R₂₃, R₂₄ and R₂₇ are each independently H or         a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted;     -   R₁₅ and R1₆ are each independently H or an optionally         substituted C₁-C₆alkyl group; and     -   R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an         optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be         taken together with the atom to which they are attached to form         a 5- to 7-membered ring optionally containing another heteroatom         selected from O, N or S; or         the stereoisomers thereof, the tautomers thereof or the         pharmaceutically acceptable salts thereof.

The term “providing” as used herein with respect to providing a compound or substance covered by the invention, designates either directly administering such a compound or substance, or administering a prodrug, derivative or analog which forms an equivalent amount of the compound or substance within the body.

The compounds of formula I may be provided by oral or parenteral administration or in any common manner known to be an effective administration of a therapeutic agent to a patient in need thereof.

The therapeutically effective amount provided in the treatment of a specific CNS disorder may vary according to the specific condition(s) being treated, the size, age and response pattern of the patient, the severity of the disorder, the judgment of the attending physician and the like. In general, effective amounts for daily oral administration may be about 0.01 to 1,000 mg/kg, preferably about 0.5 to 500 mg/kg and effective amounts for parenteral administration may be about 0.1 to 100 mg/kg, preferably about 0.5 to 50 mg/kg.

In actual practice, the compounds of the invention are provided by administering the compound or a precursor thereof in a solid or liquid form, either neat or in combination with one or more conventional pharmaceutical carriers or excipients. Accordingly, the present invention provides a pharmaceutical composition which comprises a pharmaceutically acceptable carrier and an effective amount of a compound of formula I

wherein

-   -   X is N or CR₃;     -   Y is N or CR₄;     -   R₁, R₂, R₃ and R₄ are each independently H, halogen, CN,         NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀,         NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl,         C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or         heteroaryl group each optionally substituted;     -   R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a         C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted or R₅ and R₆ maybe taken together with the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring;     -   R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each         optionally substituted;     -   R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl         or heteroaryl group each optionally substituted or R₈ and R₉ may         be taken together with the atoms to which they are attached to         form an optionally substituted 5- to 7-membered ring optionally         containing one or two heteroatoms selected from O, N or S with         the proviso that when all of R₁, R₂, R₃ and R₄ are other than         NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or         heteroaryl group or taken together with R₈ and the atoms to         which they are attached to form an optionally substituted 5- to         7-membered ring optionally containing one or two heteroatoms         selected from O, N or S;     -   R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each         optionally substituted;     -   n is 0 or an integer of 1 or 2;     -   R₁₂ is an optionally substituted aryl or heteroaryl group;     -   R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or         a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl,         cycloheteroalkyl, aryl or heteroaryl group each optionally         substituted;     -   R₁₅ and R₁₆ are each independently H or an optionally         substituted C₁-C₆alkyl group; and     -   R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an         optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be         taken together with the atom to which they are attached to form         a 5- to 7-membered ring optionally containing another heteroatom         selected from O, N or S; or         the stereoisomers thereof, the tautomers thereof or the         pharmaceutically acceptable salts thereof.

Solid carriers suitable for use in the composition of the invention include one or more substances which may also act as flavoring agents, lubricants, solubilizers, suspending agents, fillers, glidants, compression aides, binders, tablet-disintegrating agents or encapsulating materials. In powders, the carrier may be a finely divided solid which is in admixture with a finely divided compound of formula I. In tablets, the formula I compound may be mixed with a carrier having the necessary compression properties in suitable proportions and compacted in the shape and size desired. Said powders and tablets may contain up to 99% by weight of the formula I compound. Solid carriers suitable for use in the composition of the invention include calcium phosphate, magnesium stearate, talc, sugars, lactose, dextrin, starch, gelatin, cellulose, methyl cellulose, sodium carboxymethyl cellulose, polyvinylpyrrolidine, low melting waxes and ion exchange resins.

Any pharmaceutically acceptable liquid carrier suitable for preparing solutions, suspensions, emulsions, syrups and elixirs may be employed in the composition of the invention. Compounds of formula I may be dissolved or suspended in a pharmaceutically acceptable liquid carrier such as water, an organic solvent, or a pharmaceutically acceptable oil or fat, or a mixture thereof. Said liquid composition may contain other suitable pharmaceutical additives such as solubilizers, emulsifiers, buffers, preservatives, sweeteners, flavoring agents, suspending agents, thickening agents, coloring agents, viscosity regulators, stabilizers, osmo-regulators, or the like. Examples of liquid carriers suitable for oral and parenteral administration include water (particularly containing additives as above, e.g., cellulose derivatives, preferably sodium carboxymethyl cellulose solution), alcohols (including monohydric alcohols and polyhydric alcohols, e.g., glycols) or their derivatives, or oils (e.g., fractionated coconut oil and arachis oil). For parenteral administration the carrier may also be an oily ester such as ethyl oleate or isopropyl myristate.

Compositions of the invention which are sterile solutions or suspensions are suitable for intramuscular, intraperitoneal or subcutaneous injection. Sterile solutions may also be administered intravenously. Inventive compositions suitable for oral administration may be in either liquid or solid composition form.

For a more clear understanding, and in order to illustrate the invention more clearly, specific examples thereof are set forth hereinbelow. The following examples are merely illustrative and are not to be understood as limiting the scope and underlying principles of the invention in any way.

Unless otherwise stated, all parts are parts by weight. The terms HPLC and NMR designate high performance liquid chromatography and nuclear magnetic resonance, respectively. The terms THF and DMF designate tetrahydrofuran and dimethylformamide, respectively.

EXAMPLE 1 Preparation of 3-Acetyl-5-nitroindole

A solution of 5-nitroindole (10 g, 61.6 mmol) and acetyl chloride (5.8 g, 74 mmol) in methylene chloride at 0° C. is treated with tin tetrachloride (1M in CH₂Cl₂, 68 mL), stirred under N₂ for 6 h, treated with saturated NaHCO₃ to pH 9 and filtered. The filtrate is concentrated in vacuo to give a residue. The residue is dissolved in DMF and filtered. This filtrate is concentrated in vacuo to give the title product, 12.6 g (99% yield), identified by NMR and mass spectral analyses.

EXAMPLE 2 Preparation of 3-Acetyl-1-methyl-5-nitroindole

A solution of 3-acetyl-5-nitroindole (1.0 g, 5 mmol), obtained in Example 1, in DMF is treated with cesium carbonate (1.9 g, 6 mmol), stirred for 30 min. at ambient temperatures, treated with methyl iodide, stirred for 16 h, diluted with water and extracted with ethyl acetate. The extracts are combined, washed sequentially in water and brine, dried over Na₂SO₄ and concentrated in vacuo to afford the title product as a white solid, 1.0 g (93% yield), identified by NMR and mass spectral analyses.

EXAMPLE 3 Preparation of 3-Acetyl-5-aminoindole

A suspension of 3-acetyl-5-nitroindole (3.0 g, 14.7 mmol) and Raney Nickel (3.0 g) in methanol is treated dropwise with hydrazine (0.7 g, 21.9 mmol) at 0° C., stirred under N₂ for 1 h and filtered. The filtrate is concentrated in vacuo to afford the title product as an oil, 2.5 g (99% yield) identified by NMR and mass spectral analyses.

EXAMPLE 4 Preparation of 3-Acetyl-5-amino-1-methylindole

Using essentially the same procedure described in Example 3 and employing 3-acetyl-5-nitro-1-methylindole as substrate, the title product is obtained as an oil in 98% yield, identified by NMR and mass spectral analyses.

EXAMPLE 5 Preparation of 3-Acetyl-5-[(phenylsulfonyl)amino]-1H-indole

A solution of 3-acetyl-5-aminoindole (1.57 g, 9 mmol) in pyridine is treated dropwise at 0° C. with benzenesulfonyl chloride (1.25 g, 9.9 mmol), stirred for 16 h at ambient temperatures, poured into dilute aqueous HCl and extracted with ethyl acetate. The combined extracts are washed sequentially with water and brine, dried over Na₂SO₄ and concentrated in vacuo to afford the title product as a white solid, 2.8 g (99% yield), identified by NMR and mass spectral analyses.

EXAMPLE 6 Preparation of 3-Acetyl-1-methyl-5-[(phenylsulfonyl)amino]-1H-indole

Using essentially the same procedure described in Example 5 and employing 3-acetyl-5-amino-1-methylindole as substrate, the title product is obtained as a yellow solid in 41% yield, identified by NMR and mass spectral analyses.

EXAMPLE 7 Preparation of (Z)-2-{1-[5-[(Phenylsulfonyl)amino]-1H-indol-3yl]ethylidene}hydrazinecarboximidamide Hydrochloride

A mixture of 3-acetyl-5-[(phenylsulfonyl)amino]-1H-indole (3.26 g, 8.27 mmol), aminoguanidine bicarbonate (1.46 g, 10.75 mmol) and concentrated HCl (1.9 mL) in isopropanol is heated at reflux temperature for 5 h, cooled to room temperature and filtered. The filtercake is air-dried to afford the title product as a white solid, 2.5 g (75% yield) mp 198°-200° C., identified by NMR and mass spectral analyses.

EXAMPLE 8 Preparation of (Z)-2-{-1-[1-methyl-5-[(phenylsulfonyl)amino]-1H-indol-3-yl]ethylidene}hydrazinecarboximidamide Hydrochloride

Using essentially the same procedure described in Example 7 and employing 3-acetyl-1-methyl-5[(phenylsulfonyl)amino]-1H-indole as substrate, the title product is obtained as a purple solid in 70% yield, mp>300° C., identified by NMR and mass spectral analyses.

EXAMPLES 9-41 Preparation of 2{1-[5-[(Substituted-sulfonyl)amino]-1H-indol-3-yl]alkylidene}-hydrazinecarboximidamide Derivatives

Using essentially the same procedures described in Examples 1-8 hereinabove and employing the appropriate reactants, the compounds shown on Table I are obtained and identified by HPLC¹ and mass spectral analyses

¹HPLC conditions: Hewlett Packard 1100 MSD; YMC ODS-AM 2.0 mm×50 mm 5 u column at 23° C.; 3 μL injection; Solvent A: 0.02% TFA/water; Solvent B: 0.02% TFA/acetonitrile; Gradient: Time 0: 95% A; 0.3 min: 95% A; 4.7 min: 10% A; 4.9 min: 95% A; Post time 1 min. Flow rate 1.5 mL/min; Detection: 254 nm DAD; API-ES Scanning Mode Positive 150-700; Fragmentor 70 mV.

TABLE I

Ex Time No R8 R10 R12 M + H Min  9 CH₃ CH₂, C₆H₅ C₆H₅ 461 2.22 10 CH₃ CH₃ 4-NH₂—C₆H₄ 400 1.83 11 CH₃ CH₂C₆H₅ 4-NH₂—C₆H₄ 476 2.12 12 CH₃ CH₃ 5-bromothien-2-yl 470 2.10 13 CH₃ CH₂C₆H₄ 5-bromothien-2-yl 547 2.35 14 cyclo- H 5-bromothien-2-yl 525 2.40 hexane 15 CH₃ H 5-chloro-3-methyl- — — benzo[b]thien-2-yl 16 CH₃ CH₃ 5-chloro-3-methyl- 490 2.28 benzo[b]thien-2-yl 17 CH₃ CH₂C₆H₄ 5-chloro-3-methyl- 565 2.51 benzo[b]thien-2-yl 18 cyclo- H 5-chloro-3-methyl- 543 2.59 hexane benzo[b]thien-2-yl 19 CH₃ H 4-methoxyphenyl 401 1.85 20 CH₃ CH₃ 4-methoxyphenyl 415 1.96 21 CH₃ CH₃ 4-bromophenyl 464 2.12 22 CH₃ CH₂C₆H₄ 4-bromophenyl 541 2.37 23 CH₃ CH₃ 3,4-dimethoxyphenyl 445 2.13 24 CH₃ CH₂C₆H₄ 3,4-dimethoxyphenyl 521 2.18 25 CH₃ CH₃ 2-bromophenyl 463 2.05 26 CH3 CH₂C₆H₄ 2-bromophenyl 541 2.32 27 cyclo- H 2-bromophenyl 519 2.28 hexane 28 CH₃ H 4-chlorophenyl 405 2.01 29 CH₃ CH₃ 4-chlorophenyl 419 2.08 30 CH₃ CH₂C₆H₄ 4-chlorophenyl 495 2.38 31 cyclo- H 4-chlorophenyl 474 2.31 hexane 32 CH₃ H 2-naphthyl 421 2.05 33 CH₃ CH₃ 2-naphthyl 435 2.13 34 CH₃ CH₂C₆H₄ 2-naphthyl 511 2.40 35 CH₃ H 4-biphenyl 447 2.18 36 CH₃ CH₃ 4-biphenyl 461 1.82 37 CH₃ CH₂C₆H₄ 4-biphenyl 537 2.50 38 CH₃ H 2,3-dichlorothien-5-yl 445 2.11 39 CH₃ CH₃ 2,3-dichlorothien-5-yl 460 2.18 40 CH₃ CH₂C₆H₄ 2,3-dichlorothien-5-yl 536 2.48 41 cyclo- H 2,3-dichlorothien-5-yl 514 3.01 hexane

EXAMPLE 42 Preparation of 2-(2-Phenyl-1H-indol-3-ylmethylene)hydrazinecarboximidamide

A mixture of DMF (11.0 mL, 142 mmol) and phosphorous oxychloride (3.63 mL, 39 mmol) is stirred at 0° C. for 1 h, a 0.2 mL portion is pipetted into a solution of 2-phenylindole (96 mg, 0.5 mmol) in DMF at 5° C. This reaction mixture is stirred at 5°-10° C. for 1 h, quenched with water, stored at −200 for 16 h and filtered. The filtercake is washed with water and dried in vacuo to afford the 2-phenylindole-3-carboxaldehyde intermediate. A suspension of the thus-obtained 2-phenylindole-3-carboxaldehyde (44.2 mg, 0.2 mmol) in isopropanol and concentrated HCl (50 μL) is treated with aminoguanidine bicarbonate (27 mg, 0.2 mmol), heated at 80° C. for 2 h, cooled to room temperature and concentrated in vacuo. The resultant residue is purified by HPLC to afford the title product, 28 mg (20% yield), identified by mass spectral and HPLC analyses (M+H) 277; retention time 3.76 min.

¹HPLC conditions: Hewlett Packard 1100; YMC ODS-A 4.6 mm×50 mm 5 u column at 23° C.; 10 uL injection; Solvent A: 0.05% TFA/water; Solvent B: 0.05% TFA/acetonitrile; Gradient: Time 0: 98% A; 1 min: 98% A; 7 min: 10% A, 8 min: 10% A; 8.9 min: 98% A; Post time 1 min. Flow rate 2.5 mL/min; Detection: 220 and 254 nm DAD.

EXAMPLE 43 Preparation of 2-[1-(2-Phenyl-1H-indol-3-yl)ethylidene]hydrazine-carboximidamide

A mixture of 2-phenylindole (193.3 mg, 1.0 mmol) and acetyl chloride (92 μL, 1.3 mmol) in CH₂Cl₂ is treated with tin tetrachloride (97.4 μL, 1.9 mmol) at room temperature, shaken for 6 h, quenched with saturated NaHCO₃ and extracted with ethyl acetate. The extracts are combined and concentrated in vacuo to afford the 3-acetyl-2-phenylindole intermediate. A suspension of the thus-obtained 3-acetyl-2-phenylindole (47 mg, 0.2 mmol) in isopropanol and concentrated HCl (5 μL) is treated with aminoguanidine bicarbonate, heated at 80° C. for 2 h, cooled to room temperature and concentrated in vacuo. The resultant residue is purified by HPLC to afford the title product, 21.0 mg (36% yield), identified by HPLC¹ and mass spectral analyses, (M+H) 292, retention time 3.9 min.

¹HPLC conditions: same as that used in Example 42

EXAMPLES 44-76 Preparation of [(2-Arylindol-3-yl)alkylidine]hydrazinecarboximidamide Derivatives

Using essentially the same procedures described in Examples 9 and 10 and substituting the appropriate indole substrate and employing a Vilsmeier reagent or an acid chloride followed by an aminoguanidine derivative, the compounds shown in Table II are obtained and identified by mass spectral and HPLC analyses. HPLC conditions used are the same as that used in Example 42.

TABLE II

Ex M + Time No R5 R6 R7 R8 R9 H Min 44 H H H H 4-chlorophenyl 312 4.06 45 CH₂—CH₂—CH₂ H H 4-chlorophenyl 252 4.37 46 CH₂—CH₂ CH₃ H 4-chlorophenyl 352 4.29 47 CH₂—CH₂ H H 4-chlorophenyl — — 48 H H H H 3-chlo- 330 4.14 ro-4-fluoro- phenyl 49 CH₂—CH₂ CH₃ H 3-chlo- 369 4.31 ro-4-fluoro- phenyl 50 CH₂—CH₂ CH₃ H phenyl 318 3.95 51 H H H H 2-naphthyl — — 52 H H H H 4-fluorophenyl — — 53 H H H 4-chloro- 4-chlorophenyl 437 5.02 benzyl 54 H H H cyclohexyl Phenyl 360 5.0 55 H H H cyclohexyl 4-chlorophenyl 394 5.2 56 H H H cyclohexyl 3-chlo- 412 5.3 ro-4-fluoro- phenyl 57 H H H isopropyl 4-chlorophenyl 354 4.7 58 H H H isopropyl 3-chlo- 372 4.8 ro-4-fluoro- phenyl 59 H H H benzyl Phenyl 367 4.5 60 H H H benzyl 4-chlorophenyl 402 4.5 61 H H H benzyl 3-chlo- 420 4.8 ro-4-fluoro- phenyl 62 H H H isobutyl 4-chlorophenyl 368 4.9 63 H H H 2-chloro- 4-chlorophenyl 449 5.1 cinnamyl 64 H H H methyl 4-chlorophenyl 326 4.2 65 H H H methyl 3-chlo- 344 4.3 ro-4-fluoro- phenyl 66 CH₂—CH₂ CH₃ 4-chloro- Phenyl 428 4.7 phenyl 67 CH₂—CH₂ CH₃ 4-chloro- 4-chlorophenyl 462 4.01 phenyl 68 CH₂—CH₂ CH₃ isobutenyl phenyl 372 4.1 69 CH₂—CH₂ CH₃ phenethyl phenyl 422 4.8 70 CH₂—CH₂ CH₃ phenethyl 4-chlorophenyl 456 4.98 71 CH₂—CH₂ CH₃ cinnamyl phenyl 420 3.83 72 CH₂—CH₂ CH₃ cinnamyl 4-chlorophenyl 454 4.90 73 CH₂—CH₂ CH₃ 4-chloro- 4-chlorophenyl 477 4.96 benzyl 74 H H H CH₃ 4-fluorophenyl 310 0 75 H H H CH₃ 3,4-difluoro- 328 0 phenyl 76 H H H CH₃ 2-naphthyl 342 0

EXAMPLE 77 Preparation of 3-Acetyl-2-(4-chlorophenyl)-1-(phenethyl)-1H-indole

A solution of 3-acetyl-2-(4-chlorophenyl)indole (53.9 mg, 0.2 mmol) and phenethylbromide (30 μL, 0.22 mmol) in tetrahydrofuran is treated with NaH (60% dispersion in mineral oil, 24 mg, 0.6 mmol) at room temperature, shaken for 6 h, quenched with saturated NaHCO₃ and extracted with ethyl acetate. The extracts are combined and concentrated in vacuo to afford the title product, 34 mg (46% yield), identified by NMR and mass spectral analyses.

EXAMPLE 78 Preparation of 2-{[1-(2-Phenethyl)-2-phenyl-1H-indol-3-yl]ethylidene}hydrazine-carboximidamide

A suspension of 3-acetyl-2-(4-chlorophenyl)-1-(phenethyl)-1H-indole (34 mg, 0.1 mmol) in isopropanol and concentrated HCL (5 μL) is treated with aminoguanidine bicarbonate (14 mg, 0.1 mmol), heated at 80° C. for 2 h, cooled to room temperature and concentrated in vacuo. The resultant residue is purified by HPLC to afford the title compound, 20 mg (46% yield), identified by mass spectral and HPLC¹ analyses, (M+H) 396; retention time, 3.88 min.

¹HPLC conditions: same as for Example 42.

EXAMPLES 79-124 Preparation of (1-Substituted-indol-3-ylalkylidene)hydrazinecarboximidamide Derivatives

Using essentially the same procedures described in Examples 43, 77 and 78 and employing the appropriate indole substrate, acyl chloride, aryl or alkyl halide and aminoguanidine derivative, the compounds shown in Table III are obtained and identified by mass spectral analyses. HPLC conditions used are the same as that for Example 42.

TABLE III

Ex M + Time No R5 R6 R7 R8 R9 R10 H Min 79 H H H Cyclohexyl phenyl methyl 374 5.2 80 H H H Cyclohexyl phenyl phenyl 436 5.7 81 H H H Isopropyl phenyl methyl 334 4.7 82 H H H Isopropyl phenyl phenyl 396 5.2 83 H H H Benzyl phenyl methyl 382 4.8 84 H H H Benzyl phenyl phenyl 444 5.3 85 H H H Isobutyl phenyl methyl 348 4.8 86 H H H Methyl phenyl methyl 305 4.3 87 H H H Methyl phenyl phenyl 368 4.8 88 H H H 2-chlorocinnamyl phenyl phenyl 491 4.8 89 H H H H phenyl methyl 291 4.19 90 CH₂—CH₂ CH₃ H phenyl methyl 332 4.34 91 H H H H phenyl phenyl 354 4.7 92 CH₂—CH₂ CH₃ H phenyl phenyl 394 4.91 93 H H H Methyl 4-chlorophenyl benzyl 416 5.19 94 H H H H 4-chlorophenyl benzyl 402 5.12 95 CH₂—CH₂ CH₃ H 4-chlorophenyl benzyl 442 5.15 96 H H H H 4-chlorophenyl 2-chlorobenzyl 437 5.29 97 CH₂—CH₂ CH₃ H 4-chlorophenyl 2-chlorobenzyl 477 5.44 98 H H H H 4-chlorophenyl 4-methylbenzyl 416 5.20 99 CH₂—CH₂ CH₃ H 4-chlorophenyl 4-methylbenzyl 0 5.37 100 H H H Methyl 4-chlorophenyl 4-(2-methylthiazolyl)-methyl 436 4.54 101 H H H H 4-chlorophenyl 4-(2-methylthiazolyl)-methyl 423 4.45 102 CH₂—CH₂ CH₃ H 4-chlorophenyl 4-(2-methylthiazolyl)-methyl 464 5.14 103 H H H H 4-chlorophenyl ethyl 340 4.43 104 CH₂—CH₂ CH₃ H 4-chlorophenyl ethyl 380 4.82 105 H H H H 4-chlorophenyl isobutyl 368 4.97 106 CH₂—CH₂ CH₃ H 4-chlorophenyl isobutyl 404 4.45 107 H H H Methyl 4-chlorophenyl cyanoethyl 379 4.19 108 H H H H 4-chlorophenyl cyanoethyl 365 4.03 109 CH₂—CH₂ CH₃ H 4-chlorophenyl cyanoethyl 405 4.27 110 H H H H 4-chlorophenyl phenethyl 416 5.13 111 CH₂—CH₂ CH₃ H 4-chlorophenyl phenethyl 456 5.32 112 CH₂—CH₂ CH₃ H 4-chlorophenyl 3-butenyl 406 5.11 113 H ethanol H H 4-chlorophenyl H 356 3.73 114 CH₃ ethanol H H 4-chlorophenyl H 370 3.83 115 H cyclopentyl H H 4-chlorophenyl H 380 4.66 116 CH₃ cyclopentyl H H 4-chlorophenyl H 394 4.75 117 H benzyl H H 4-chlorophenyl H 402 4.79 118 CH₃ benzyl H H 4-chlorophenyl H 416 4.66 119 H n-propyl H H 4-chlorophenyl H 354 4.57 120 CH₃ n-propyl H H 4-chlorophenyl H 368 4.48 121 H CH₃ H H 4-chlorophenyl H 326 4.18 122 CH₃ CH₃ H H 4-chlorophenyl H 340 4.04 123 H n-pentyl H H 4-chlorophenyl H 382 4.96 124 CH₃ n-pentyl H H 4-chlorophenyl H 396 4.86

EXAMPLE 125 Preparation of 5-Chloro-2-(2,4-dichlorophenyl)-1H-indole

A mixture of 2,4-dichloroacetophenone (378 mg, 2.0 mmol), p-chloro-phenylhydrazine (358 mg, 2.0 mmol and polyphosphoric acid (PPA) (0.5 mL) is heated at 100° C. for 8 h, cooled to room temperature, diluted with water, stirred briefly, allowed to stand at room temperature for 16 h and filtered. The filtercake is washed with water and air-dried to afford the title compound, 320 mg (54% yield), identified by NMR and mass spectral analyses.

EXAMPLE 126 Preparation of 5-Chloro-2-(2,4-dichlorophenyl)-1-methyl-1H-indole

A mixture of 5-chloro-2-(2,4-dichlorophenyl)-1H-indole (160 mg, 0.54 mmol) and methyl iodide (124 μL, 2.0 mmol) in tetrahydrofuran is treated with NaH (60% dispersion in mineral oil, 160 mg, 4.0 mmol), shaken at room temperature for 16 h, quenched with water and extracted with ethyl acetate. The extracts are combined and concentrated in vacuo to afford the title product which is used as is in Example 128.

EXAMPLE 127 Preparation of 2-{[5-Chloro-2-(2,4-dichlorophenyl)-1H-indol-3-yl]ethylidene}hydrazinecarboximidamide

A solution of 5-chloro-2-(2,4-dichlorophenyl)-1H-indole (160 mg, 0.54 mmol) and acetyl chloride (80 μL, 1.2 mmol) in CH₂Cl₂ is treated with tin tetrachloride (1.0 M solution in CH₂Cl₂, 1 mL), shaken at room temperature for 6 h, quenched with saturated NaHCO₃ and extracted with ethyl acetate. The extracts are combined and concentrated in vacuo. The resultant residue is suspended in isopropanol and concentrated HCl (100 μL), treated with aminoguanidine bicarbonate (100 mg, 0.75 mmol), heated at 80° C. for 2 h, cooled to room temperature and concentrated in vacuo. This residue is purified by HPLC to afford the title compound, 7.0 mg (3% yield), identified by HPLC¹ and mass spectral analyses; (M+H) 395; retention time 4.51 min.

¹HPLC conditions: same as that for Example 42.

EXAMPLE 128 Preparation of 2-{[5-Chloro-2-(2,4-dichlorophenyl)-1-methyl-1H-indol-3-yl]ethylidene}hydrazinecarboximidamide

Using essentially the same procedure described in Example 127 and substituting 5-chloro-2-(2,4-dichlorophenyl)-1-methyl-1H-indole as substrate, the title product is obtained and identified by HPLC¹ and mass spectral analyses, (M+H) 408/410; retention time 4.96 min.

¹HPLC conditions: are the same as that used in Example 42.

EXAMPLES 129-150 Preparation of [(2- and/or 5-Substituted-indol-3-yl)ethylidene]hydrazine-caroboximidamide Derivatives

Using essentially the same procedures described in Examples 125-128 and employing the appropriate starting materials, the compounds shown in Table IV are obtained and identified by HPLC and mass spectral analyses. HPLC conditions are the same as that for Example 42.

TABLE IV

Ex Time No. R2 R9 R10 M + H Min. 129 H 2,4-dichlorophenyl H 360 4.21 130 Br 2,4-dichlorophenyl H 438/440 4.43 131 H 4-methylphenyl H 306 4.05 132 Br 4-methylphenyl H 384/386 4.38 133 H 3-methylthien-2-yl H 312 3.95 134 Cl 4-bromophenyl H 404/406 4.38 135 H 4-bromophenyl H 370/372 4.25 136 Br 4-bromophenyl H 448/450 4.60 137 Br 4-chlorophenyl H 404/406 4.53 138 H 4-methoxyphenyl H 322 3.95 139 H 3-thienyl H 350 3.93 140 Br 3-thienyl H 376/378 4.27 141 Cl 4-biphenyl H 402 4.76 142 Cl 3,4-dichlorophenyl H 394 4.55 143 Cl 4-biphenyl CH₃ 416 — 144 Cl 3,4-dichlorophenyl CH₃ 408/410 — 145 H 3,4-dichlorophenyl CH₃ 374 — 146 H 3-methylthien-2-yl CH₃ 326 — 147 Cl 4-bromophenyl CH₃ 418/420 — 148 H 4-bromophenyl CH₃ 384/386 — 149 Cl 4-chlorophenyl CH₃ 374/376 — 150 H 4-chlorophenyl CH₃ — —

EXAMPLE 151 Preparation of 6-Chloro-4-oxo-1,2,3,4-tetrahydrocarbazole

A suspension of p-chlorophenylhydrazine hydrochloride (8.06 g, 45 mmol) in water is added over a 10 min. period to a solution of 1,3-cyclohexanedione (5.05 g, 45 mmol) in water, stirred for 16 h and filtered. The filtercake is washed with water and air-dried. The thus-obtained cyclohexane-1,3-dione mono-(4-chlorophenyl)-hydrazone (45 mmol th.) is dissolved in trifluoroacetic acid (TFA) (30 mL), heated at 80° C. for 16 h, cooled to room temperature, poured into ice-water and filtered. The filtercake is air-dried and recrystallized from ethanol/water to afford the title product as a tan solid, 4.2 g (42% yield) identified by NMR and mass spectral analyses.

EXAMPLE 152 Preparation of 2-(6-Chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazine-carboximidamide

A suspension of 6-chloro-4-oxo-1,2,3,4-tetrahydrocarbazole (21.9 mg, 0.1 mmol) in isopropanol and concentrated HCl (50 μL) is treated with aminoguanidine bicarbonate (20.4 μg, 0.15 mmol), heated at 80° C. for 4 h, cooled to room temperature and concentrated in vacuo. The resultant residue is purified by HPLC to give the title compound, 15.8 mg (49% yield), identified by mass spectral and HPLC analyses, (M+H) 276; retention time 3.72 min.

EXAMPLES 153-183 Preparation of Substituted-1,2,3,9-tetrahydro-4H-carbazol Aminoguanidine Derivatives

Using essentially the same procedures described in Examples 118 and 119 and substituting the appropriate phenyl hydrazine, 1,3-cyclohexanedione and aminoguanidine reagents, the compounds shown in Table V are obtained and identified by mass spectral and HPLC analyses. HPLC conditions are the same as that in Example 42.

TABLE V

Ex Time No R2 R5 R6 R7 A b M + H Min 153 Cl CH₂—CH₂ H H H 302 3.87 154 Cl CH₂—CH₂ CH₃ H H 316 3.87 155 OCH₃ CH₂—CH₂ H H H — — 156 F H H H H H 260 3.51 157 F CH₂—CH₂ H H H 286 3.70 158 F CH₂—CH₂ CH₃ H H 300 3.57 159 Br H H H H H 320/322 3.79 160 Br CH₂—CH₂ CH₃ H H 360/362 4.22 161 H H H H H H 242 3.39 162 OCH₃ H H H H H — — 163 CH₃ H H H CH₃ CH₃ 284 3.99 164 CH₃ H H H C₆H₅ H 332 4.39 165 CH₃ H H H H H 256 4.27 166 iso- H H H CH₃ CH₃ 312 4.40 propyl 167 iso- H H H C₆H₅ H 360 4.67 propyl 168 OCF₃ H H H CH₃ CH₃ 354 4.34 169 Br H H H CH₃ CH₃ 349 4.10 170 Br H H H C₆H₅ H 397/399 4.48 171 Cl H H H CH₃ CH₃ 304 4.05 172 Cl H H H C₆H₅ H 352 4.38 173 F H H H CH₃ CH₃ 288 3.86 174 CH₃ CH₂—CH₂ CH₃ CH₃ CH₃ 324 3.94 175 CH₃ CH₂—CH₂ CH₃ C₆H₅ H 372 4.38 176 CH₃ CH₂—CH₂ CH₃ H H 296 3.56 177 iso- CH₂—CH₂ CH₃ CH₃ CH₃ 352 4.44 propyl 178 iso- CH₂—CH₂ CH₃ C₆H₅ H 400 4.79 propyl 179 iso- CH₂—CH₂ CH₃ H H 324 4.1  propyl 180 F CH₂—CH₂ CH₃ C₆H₅ H 376 4.32 181 Cl H n-pentyl H H H 346 4.76 182 Cl H benzyl H H H 306 4.76 183 Cl H cyclopentyl H H H 344 4.72

EXAMPLE 184 Preparation of 7-Chloro-3,4-dihydrocyclopenta[b]indol-1(2H)-one 4,5-dihydro-1H-imidazol-2-yl-(methyl)hydrazone

Using essentially the same procedures described in Examples 151 and 152 and substituting 1,3-cyclopentadione and the appropriate aminoguanidine derivative, the title compound is obtained and identified by mass spectral and HPLC¹ analyses, (M+H) 302; retention time 3.60 min.

¹HPLC conditions: are the same as that for Example 42.

EXAMPLE 185 Evaluation of 5-HT6 Binding Affinity of Test Compounds

The affinity of test compounds for the serotonin 5-HT6 receptor is evaluated in the following manner. Cultured Hela cells expressing human cloned 5-HT6 receptors are harvested and centrifuged at low speed (1,000×g) for 10.0 min to remove the culture media. The harvested cells are suspended in half volume of fresh physiological phosphate buffered saline solution and recentrifuged at the same speed. This operation is repeated. The collected cells are then homogenized in ten volumes of 50 mM Tris.HCl (pH 7.4) and 0.5 mM EDTA. The homogenate is centrifuged at 40,000×g for 30.0 min and the precipitate is collected. The obtained pellet is resuspended in 10 volumes of Tris.HCl buffer and recentrifuged at the same speed. The final pellet is suspended in a small volume of Tris.HCl buffer and the tissue protein content is determined in aliquots of 10-25 μl volumes. Bovine Serum Albumin is used as the standard in the protein determination according to the method described in Lowry et al., J. Biol. Chem., 193:265 (1951). The volume of the suspended cell membranes is adjusted to give a tissue protein concentration of 1.0 mg/ml of suspension. The prepared membrane suspension (10 times concentrated) is aliquoted in 1.0 ml volumes and stored at −70° C. until used in subsequent binding experiments.

Binding experiments are performed in a 96 well microtiter plate format, in a total volume of 200 μl. To each well is added the following mixture: 80.0 μl of incubation buffer made in 50 mM Tris.HCl buffer (pH 7.4) containing 10.0 mM MgCl₂ and 0.5 mM EDTA and 20 μl of [³H]-LSD (S.A., 86.0 Ci/mmol, available from Amersham Life Science), 3.0 nM. The dissociation constant, K_(D) of the [³H]LSD at the human serotonin 5-HT6 receptor is 2.9 nM, as determined by saturation binding with increasing concentrations of [³H]LSD. The reaction is initiated by the final addition of 100.0 μl of tissue suspension. Nonspecific binding is measured in the presence of 10.0 μM methiothepin. The test compounds are added in 20.0 μl volume.

The reaction is allowed to proceed in the dark for 120 min at room temperature, at which time, the bound ligand-receptor complex is filtered off on a 96 well unifilter with a Packard Filtermate® 196 Harvester. The bound complex caught on the filter disk is allowed to air dry and the radioactivity is measured in a Packard TopCount® equipped with six photomultiplier detectors, after the addition of 40.0 μl Microscint®-20 scintillant to each shallow well. The unifilter plate is heat-sealed and counted in a PackardTopCount® with a tritium efficiency of 31.0%.

Specific binding to the 5-HT6 receptor is defined as the total radioactivity bound less the amount bound in the presence of 10.0 μM unlabeled methiothepin. Binding in the presence of varying concentrations of test compound is expressed as a percentage of specific binding in the absence of test compound. The results are plotted as logit % bound versus log concentration of test compound. Nonlinear regression analysis of data points with a computer assisted program Prism® yields both the IC₅₀ and the K_(i) values of test compounds with 95% confidence limits.

The amount of displacement by the test compound is given in percent (%) inhibition and is derived from the following equation: ${\%\quad{inhibition}} = {\left( {1 - \frac{B_{0} - {NSB}}{{TB} - {NSB}}} \right)100}$ where B₀ is the amount of CPM bound in the presence of the testing agent. NSB represents the CPM bound in the presence of a saturating concentration of a displacer and TB represents the total amount of CPM bound at zero (0) concentration of test compound.

Alternatively, a linear regression line of decline of data points is plotted, from which the IC₅₀ value can be read off and the K_(i) value determined by solving the following equation: $K_{i} = \frac{{IC}_{50}}{1 + {L/K_{D}}}$ where L is the concentration of the radioactive ligand used and K_(D) is the dissociation constant of the ligand for the receptor, both expressed in nM. Using this assay, the % inhibition and K_(i) values shown in Table VI are obtained.

TABLE VI Test Compound Dose 5-HT6 Binding Ki (Ex. No.) (nM) % Inhibition (nM)  7 — — 1.0  8 — — 2.0  9 1000 94.9 —  10 1000 98.7 4.0  11 1000 93.6 —  12 1000 99.0 2.0  13 1000 92.0 —  14 1000 90.3 —  15 1000 — —  16 1000 98.7 7.0  17 1000 92.5 —  18 1000 72.2 —  19 1000 97.4 1.0  20 1000 99.0 3.0  21 1000 99.2 3.0  22 1000 85.5 —  23 1000 99.4 3.0  24 1000 89.9 —  25 1000 99.0 1.0  26 1000 92.6 —  27 1000 82.2 —  28 1000 94.9 —  29 1000 98.4 4.0  30 1000 88.9 —  31 1000 81.2 —  32 1000 96.3 —  33 1000 96.8 —  34 1000 84.4 —  35 1000 96.4 —  36 1000 93.3 —  37 1000 79.7 —  38 1000 99.0 1.0  39 1000 95.6 —  40 1000 87.3 —  41 1000 79.9 —  42 1000 82.1 —  43 1000 93.3 —  44 — — 18  45 1000 68.5 —  46 1000 96.5 10  47 — — 20.2  48 1000 88.6 —  49 1000 93.8 —  50 1000 96.2 —  51 — — 109  52 — — 29  53 1000 33.7 —  54 1000 27.0 —  55 1000 28.5 —  56 1000 33.9 —  57 1000 74.6 —  58 1000 71.2 —  59 1000 24.4 —  60 1000 49.5 —  61 1000 83.9 —  62 1000 78.2 —  63 1000 31.7 —  64 1000 98.5 17  65 1000 87.2 —  66 1000 18.1 —  67 1000 35.2 —  68 1000 24.8 —  69 1000 23.0 —  70 1000 33.9 —  71 1000 30.0 —  72 1000 40.9 —  73 1000 37.5 —  74 10 38.3 —  75 1000 73.2 —  76 1000 78.2 —  78 1000 84.2 —  79 1000 31.3 —  80 1000 8.7 —  81 1000 43.2 —  82 1000 21.5 —  83 1000 31.0 —  84 1000 22.9 —  85 1000 71.8 —  86 1000 99.4 19  87 1000 31.3 —  88 1000 37.5 —  89 1000 70.6 —  90 1000 99.9 11  91 1000 24.0 —  92 1000 17.8 —  93 1000 22.3 —  94 1000 19.7 —  95 1000 20.0 —  96 1000 15.6 —  97 1000 0.4 —  98 1000 21.1 —  99 1000 5.7 — 100 1000 31.5 — 101 1000 24.0 — 102 1000 62.7 — 103 1000 80.1 — 104 1000 100.0 —   105a 1000 21.9 —   105b 1000 13.7 — 107 1000 87.2 — 108 1000 92.0 — 109 1000 99.1 — 110 1000 20.9 — 111 1000 37.5 — 112 1000 85.1 — 113 1000 84.1 — 114 1000 31.6 — 115 1000 49.5 — 116 1000 59.5 — 117 1000 69.0 — 118 1000 56.2 — 119 1000 86.0 — 120 1000 49.9 — 121 1000 90.5 — 122 1000 38.4 — 123 1000 70.4 — 124 1000 74.0 — 127 100 50.6 — 128 100 57.3 — 129 100 44.7 — 130 100 49.2 — 131 100 87.7 12 132 100 90.0 23 133 100 63.2 — 134 100 82.8 26 135 100 75.7 30 136 100 79.0 53 137 100 80.7 36 138 100 60.5 — 139 100 60.1 — 140 100 49.0 — 141 100 33.6 — 142 100 42.5 — 143 100 34.6 — 144 100 47.6 — 145 100 55.1 — 146 100 46.1 — 147 100 59.7 — 148 100 68.1 — 149 100 76.4 18 150 100 66.6 — 152 1000 99.1 — 153 1000 97 — 154 1000 87.1 — 156 1000 98.8 — 157 1000 96.3 — 158 1000 68.7 — 159 10 61.1 — 160 1000 76 — 161 10 39.5 — 162 1000 98 4.7 163 100 38.5 — 164 100 27.6 — 165 100 57.2 — 166 100 27.3 — 167 100 35.2 — 168 100 26 — 169 100 33.9 — 170 100 24.4 — 171 100 30.7 — 172 100 24.6 — 173 100 26.7 — 174 100 25.5 — 175 100 18.6 — 176 100 24.2 — 177 100 22.9 — 178 100 25.6 — 179 100 5.6 — 180 100 11.5 — 181 100 47.0 — 182 100 47.3 — 183 100 55.3 — 184 100 19.78 — 

1. A compound of formula I

wherein X is CR₃; Y is CR₄; R₁, R₂, R₃ and R₄ are each independently H, halogen, CN, NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀, NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted or R₅ and R₆ maybe taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring; R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each optionally substituted; R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl or heteroaryl group each optionally substituted or R₈ and R₉ may be taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S with the proviso that when all of R₁, R₂, R₃ and R₄ are other than NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or heteroaryl group or taken together with R₈ and the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S; R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each optionally substituted; n is 0 or an integer of 1 or 2; R₁₂ is an optionally substituted aryl or heteroaryl group; R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₁₅ and R₁₆ are each independently H or an optionally substituted C₁-C₆alkyl group; and R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be taken together with the atom to which they are attached to form a 5- to 7-membered ring optionally containing another heteroatom selected from O, N or S; or a stereoisomer thereof, a tautomer thereof or a pharmaceutically acceptable salt thereof.
 2. The compound according to claim 1 wherein R₁₀ is H.
 3. The compound according to claim 1 wherein R₂ is NR₁₁SO₂R₁₂.
 4. The compound according to claim 1 wherein R₈ and R₉ are taken together with the atoms to which they are attached to form a 5- to 7-membered ring.
 5. The compound according to claim 2 wherein R₉ is an optionally substituted phenyl group.
 6. The compound according to claim 3 wherein R₁₀ and R₁₁ are H.
 7. The compound according to claim 4 wherein R₂ is H, C₁-C₆alkoxy or NR₁₁SO₂R₁₂.
 8. The compound according to claim 1 selected from the group consisting of: (Z)-2-[1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; 2-((Z)-1-{1-methyl-5-[(phenylsulfonyl)amino]-1H-indol-3-yl}ethylidene)hydrazinecarboximidamide; (Z)-2-[1-[5-[(4-biphenylsulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; (Z)-2-[1-[5-[(4-bromophenylsulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; (Z)-2-[1-[5-[(5-bromothiophene-2-sulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazine-carboximidamide; (Z)-2-[1-[5-[(5-chloro-2-methoxybenzenesulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; (Z)-2-[1-[5-[(2,5-dichlorobenzenesulfonyl)amino]-1H-indol-3-yl]ethylidene]hydrazinecarboximidamide; (Z)-2-{cyclohexyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]methylidene}hydrazinecarboximidamide; (Z)-2-{2-methyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]propylidene}hydrazinecarboximidamide; (Z)-2-{2-phenyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]ethylidene}hydrazinecarboximidamide; (Z)-2-{3-methyl-1-[5-[(phenylsulfonyl)amino]-1H-indol-3-yl]butylidene}hydrazinecarboximidamide; 2-[1-[5-[(phenylsulfonyl)amino]-1H-indole-3-carbaldehyde]-1,4,5,6-tetrahydro-pyrimidin-2-ylhydrazone; 2-[1-[5-[(phenylsulfonyl)amino]-1H-indole-3-carbaldehyde]-4,5-dihydro-1H-imidazol-2-yl(methyl)hydrazone; 2-(2-phenyl-1H-indol-3-ylmethylene)hydrazinecarboximidamide; 2-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]hydrazinecarboximidamide; N′-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; N-[2-(4-chlorophenyl)-1H-indol-3-ylmethylene]-N′-(4,5-dihydro-1H-imidazol-2-yl)hydrazine; N′-[2-(3-chloro-4-fluorophenyl)-1H-indol-3-ylmethylene]-N-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; N-(4,5-dihydro-1H-imidazol-2-yl)-N′-(2-phenyl-1H-indol-3-ylmethylene)-N-methylhydrazine; 2-{[2-(naphthalen-2-yl)-1H-indol-3-yl]methylene}hydrazinecarboximidamide; 2-[2-(4-fluorophenyl)-1H-indol-3-ylmethylene]hydrazinecarboximidamide; 2-{1-[2-(4-chlorophenyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; 2-[1-(1-methyl-2-phenyl-1H-indol-3-yl)-ethylidene]hydrazinecarboximidamide; N-(4,5-dihydro-1H-imidazol-2-yl)-N′-[(1-methyl-2-phenyl-1H-indol-3-yl)-methylene]-N-methylhydrazine; N-{[2-(4-chloro-phenyl)-1-ethyl-1H-indol-3-yl]-methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; 2-{[2-(4-chlorophenyl)-1-(2-cyanoethyl)-1H-indol-3-yl]methylene}hydrazinecarboximidamide; N-{[2-(4-chlorophenyl)-1-(2-cyanoethyl)-1H-indol-3-yl]methylene}-N′-(4,5-dihydro-1H-imidazol-2-yl)-N-methylhydrazine; 2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-cyclopentyl-N′-methyl-1hydrazinecarboximidamide; 2-{[5-bromo-2-(p-tolyl)-1H-indol-3-yl]-ethylidene}hydrazinecarboximidamide; 2-(6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; 6-chloro-1,2,3,9-tetrahydro-4H-carbazol-4-one 4,5-dihydro-1H-imidazol-2-ylhydrazone; 2-(6-fluoro-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)hydrazinecarboximidamide; 6-fluoro-1,2,3,9-tetrahydro-4H-carbazol-4-one 4,5-dihydro-1H-imidazol-2-ylhydrazone; N-(6-methoxy-1,2,3,9-tetrahydro-4H-carbazol-4-ylidene)carbonohydrazonic diamide; a stereoisomer thereof; the tautomers a tautomer thereof; and a pharmaceutically acceptable salt thereof.
 9. A method for the treatment of a disorder of the central nervous system related to or affected by the 5-HT6 receptor wherein said disorder is depression or anxiety in a patient in need thereof which comprises providing to said patient a therapeutically effective amount of a compound of formula I

wherein X is CR₃; Y is CR₄; R₁, R₂, R₃ and R₄ are each independently H, halogen, CN, NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀, NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted or R₅ and R₆ maybe taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring; R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each optionally substituted; R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl or heteroaryl group each optionally substituted or R₈ and R₉ may be taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S with the proviso that when all of R₁, R₂, R₃ and R₄ are other than NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or heteroaryl group or taken together with R₈ and the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S; R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each optionally substituted; n is 0 or an integer of 1 or 2; R₁₂ is an optionally substituted aryl or heteroaryl group; R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₁₅ and R₁₆ are each independently H or an optionally substituted C₁-C₆alkyl group; and R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be taken together with the atom to which they are attached to form a 5- to 7-membered ring optionally containing another heteroatom selected from O, N or S; or a stereoisomer thereof, a tautomer thereof or a pharmaceutically acceptable salt thereof.
 10. The method according to claim 9 wherein said disorder is anxiety.
 11. The method according to claim 9 wherein said disorder is depression.
 12. The method according to claim 9 having a formula I compound wherein R₁₀ is H.
 13. The method according to claim 12 having a formula I compound wherein R₂ is H, C₁-C₆alkoxy or NR₁₁SO₂R₁₂.
 14. A pharmaceutical composition which comprises a pharmaceutically acceptable carrier and an effective amount of a compound of formula I

wherein X is CR₃; Y is CR₄; R₁, R₂, R₃ and R₄ are each independently H, halogen, CN, NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(N)R₂₀, NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted or R₅ and R₆ maybe taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring; R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each optionally substituted; R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl or heteroaryl group each optionally substituted or R₈ and R₉ may be taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S with the proviso that when all of R₁, R₂, R₃ and R₄ are other than NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or heteroaryl group or taken together with R₈ and the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S; R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each optionally substituted; n is 0 or an integer of 1 or 2; R₁₂ is an optionally substituted aryl or heteroaryl group; R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₁₅ and R₁₆ are each independently H or an optionally substituted C₁-C₆alkyl group; and R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be taken together with the atom to which they are attached to form a 5- to 7-membered ring optionally containing another heteroatom selected from O, N or S; or a stereoisomer thereof, a tautomer thereof or a pharmaceutically acceptable salt thereof.
 15. The composition according to claim 14 having a formula I compound wherein R₁₀ is H.
 16. The composition according to claim 15 having a formula I compound wherein R₂ is H, C₁-C₆alkoxy or NR₁₁SO₂R₁₂.
 17. The composition according to claim 16 wherein R₉ is an optionally substituted phenyl group.
 18. The composition according to claim 17 having a formula I compound wherein R₈ and R₉ are taken together with the atoms to which they are attached to form a 5- to 7-membered ring.
 19. A process for the preparation of a compound of formula I

wherein X is CR₃; Y is CR₄; R₁, R₂, R₃ and R₄ are each independently H, halogen, CN, NR₁₁SO₂R₁₂, OCO₂R₁₃, CO₂R₁₄, CONR₁₅R₁₆, NR₁₇COR₁₈, SO_(n)R₂₀, NR₂₁R₂₂, OR₂₃, COR₂₄ or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₅, R₆, R₇, R₁₁ and R₁₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₁₂cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted or R₅ and R₆ maybe taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring; R₈ is H or a C₁-C₆alkyl or C₃-C₁₀cycloalkyl group each optionally substituted; R₉ is H, halogen, CN, NO₂, NR₂₅R₂₆, OR₂₇ or a C₁-C₆alkyl, aryl or heteroaryl group each optionally substituted or R₈ and R₉ may be taken together with the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S with the proviso that when all of R₁, R₂, R₃ and R₄ are other than NR₁₁SO₂R₁₂ then R₉ must be an optionally substituted aryl or heteroaryl group or taken together with R₈ and the atoms to which they are attached to form an optionally substituted 5- to 7-membered ring optionally containing one or two heteroatoms selected from O, N or S; R₁₀ is H or a C₁-C₆ alkyl, aryl or heteroaryl group each optionally substituted; n is 0 or an integer of 1 or 2; R₁₂ is an optionally substituted aryl or heteroaryl group; R₁₃, R₁₄, R₁₈, R₂₀, R₂₃, R₂₄ and R₂₇ are each independently H or a C₁-C₆alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, C₃-C₆cycloalkyl, cycloheteroalkyl, aryl or heteroaryl group each optionally substituted; R₁₅ and R₁₆ are each independently H or an optionally substituted C₁-C₆alkyl group; and R₁₉, R₂₁, R₂₂, R₂₅ and R₂₆ are each independently H or an optionally substituted C₁-C₄alkyl group or R₂₁ and R₂₂ may be taken together with the atom to which they are attached to form a 5- to 7-membered ring optionally containing another heteroatom selected from O, N or S which process comprises reacting a compound of formula II

wherein X, Y, R₁, R₂, R₈, R₉ and R₁₀ are described hereinabove with an aminoguanidine derivative of formula III

wherein R₅, R₆ and R₇ are described hereinabove in the presence of an acid optionally in the presence of a solvent. 